Field of Invention
The invention relates to a liquid crystal display (LCD) apparatus. More particularly, the invention relates to an LCD apparatus with brightness/luminance holding ratio compensation and a driving method thereof.
Description of Related Art
In recent years, a liquid crystal display (LCD) apparatus has been applied in many areas, including a notebook personal computer, a monitor, a vehicular navigation device, a functional calculator, various sizes of TV sets, a mobile phone and an electronic message board. Particularly, the current thin and light or portable electronic products have become a new trend in the market. The LCD apparatus has a smaller volume and thickness than the prior CRT (cathode-ray tube) display apparatus, so the LCD apparatus has been widely applied.
In the development of the current electronic display technology, the power consumption of the display apparatus is emphasized, so the LCD apparatus with low power consumption better meets the requirements of a user for energy saving and environment protection. Particularly, in a portable display apparatus (such as a cellular phone, a smart phone, a PDA (personal digital assistant), an e-book and a tablet computer), the power consumption of the LCD module directly influences the endurance of the entire apparatus. Particularly, in the current large-size, thin and light display apparatus, the LCD module with the low power consumption and high efficiency is urgently demanded.
The current LCD apparatus generally has a certain refresh rate or frame rate. Generally, the LCD apparatus adopts the rate of 50-70 Hz. That is, the frame refreshes 50-70 times per second.
In other words, even if the display frame of the LCD apparatus has no change or few changes, the display driving circuit may still periodically refresh a display signal of each pixel of the display module at the rate of 60 times per second. Thus, unnecessary energy consumption is generated.
For a current general TFT-LCD (thin film transistor liquid crystal display) apparatus on the market, the power consumption is mainly caused by the LCD panel, the driving circuit and the backlight module. Taking the 10.1-inch TFT-LCD apparatus with a resolution of 1366×800 as an example, the power consumption of the LCD panel and the driving circuit is approximately between 1000 mW and 2000 mW. On the other hand, the power consumption of the backlight module is approximately between 2000 mW and 3000 mW.
Although a polarity inversion driving manner, e.g. a row inversion driving manner or a frame inversion driving manner, has been proposed in this industry directed for the driving circuit, and an area scanning backlight manner has been proposed directed for the backlight module, the above manners have limited effects. Therefore, those in the industry are endeavoring to find an LCD apparatus having a stable display effect and low energy consumption and a display driving method thereof.
In a display frame cycle between two display signal refreshes, the potential levels of the storage capacitance in the LCD apparatus may gradually decrease over time, resulting in the transmittance variance of the LCD panel. For example, in a normally white mode, the transmittance increases over time, and in a normally black mode, the transmittance decreases over time, thus probably resulting in the inconsistent or unstable display brightness/luminance in a display frame cycle and further causing the blink and screen flicker phenomena. Particularly, at the low refresh rate, the potential-levels attenuation degree of the storage capacitance is more apparent, and consequently, the problem of screen flicker is severe.